AAA combination - three angles
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  • this is not a valid test for triangle congruency.

AAS combination - two angles & a side that is not between them
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  • this is a valid test for triangle congruency.

SSA combination - two sides & an angle that is not between them ( that is, an angle opposite on of the two sides )

  • this is not a valid test for triangle congruency.

HL (Hypotenuse-Leg) Congruence Theorem - if the hypotenuse and a leg of a right triangle are congruent to the hypotenuse and a leg of another right triangle, then the two triangles are congruent.

AAS(Angle side Angle): If two angles and a nonincuded side of one triangle are congruent to the correspnding angles and nonincluded side of another triangle,then the triangles are congruent.

HL(Hypotenuse -Leg theorem) IF the hypotenuse and a leg of a right triangle are congruent to the hypotenuse and a leg of another right triangle, then the two triangles are congruent

Side - Angle - Side (SAS) Congruence
Included angle means between the sides marked congruent.
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